Thursday 21 March 2013

Milk, cancer and hype

The headlines were striking enough, for example the Daily Mail declared that 'Breast cancer patients who eat cheese, yogurts or ice cream could HALVE their chances of survival', while the Daily Mirror ran the headline 'High-fat dairy food increases risk of death in breast cancer patients'. The question is are these scary headlines warranted?

The source of the headlines is a study that looked at dairy intake in women after they had been diagnosed with early-stage invasive breast cancer between 1997 and 2000. These women were asked to fill in questionnaires about their diet, and these were followed up five or six years later. The researchers then looked at the associations with dairy intake and outcomes. The reported outcome was that intake of high-fat dairy was associated with a great risk of death, both from cancer and other causes.

The first thing to say is that this paper is not open access. It's published in the Journal of the National Cancer Institute (JNCI), which is a tax-payer funded body, and it's outrageous that scientific research like this is kept away from the public. When there's a story as potentially important as this then there's no excuse for keeping the data behind a pay-wall. US tax-payers should be demanding that the JNCI switch to open access publishing immediately.

That said, and without access to the full paper, there are some comments to make on what's reported in the abstract of the paper. Firstly this is a study that depends on questionnaires. This is one of the most unreliable sources of information on long term diet that there is. It depends on people being able to accurately remember what they eat and drink, and that they're not lying to themselves or trying to impress the people running the survey. In a long time frame, it also means the researchers have to make assumptions about the long periods between questionnaires. Remember, the researchers are trying to establish the cumulative intake of dairy.

Tuesday 12 March 2013

Itraconazole - Anti-fungal and anti-cancer

One of the common themes of this site is the use of existing drugs as anti-cancer agents. Given the many years and millions of dollars it takes to get new drugs from the lab and into early phase human trials, it makes a lot of sense to re-look at existing, approved drugs to see if they can be re-purposed as anti-cancer therapies. Prominent examples of such drugs include metformin (used in diabetes), aspirin (pain killer), beta blockers (used for treating hypertension) and mebendazole (used as an anti-parasitic agent).

The latest example is the anti-fungal drug Itraconazole. A Phase II trial has just been reported in a paper in the Oncologist - freely accessible to all here: http://theoncologist.alphamedpress.org/content/18/2/163.full. The drug was used to treat advanced prostate cancer (metastatic castration-resistant prostate cancer to be exact). Two dosing schedules were used, low-dose (200 mg/day) or high-dose (600 mg/day), and the men were treated for 24 weeks and then assessed for a reduction in PSA and, more importantly, for progression free survival.

The low dose arm of the trial was abandoned early because of the low levels of response, however the higher dose arm continued to completion. The results were fairly impressive. The primary end-point of the study was stopping the increase in PSA levels, and this was acheived in 48% of men on the high dose (12 of 25 men). The main secondary end point was freedom from disease progression (which is the more important measure overall), and here the result was that 24-week PFS rate was estimated to be 61.6%.

Wednesday 6 March 2013

The 2-Day Diet

It may seem odd to find a review of a diet book on a web site devoted to cancer, but there are good reasons for looking at this book. Firstly, it's an accepted fact that there is a strong link between obesity, metabolism and cancer. Secondly, there is an increasing view among some researchers that cancer is a metabolic syndrome, and that cancers are associated with a whole set of metabolic changes, both in the tumour and the surrounding tissues. Cancer and metabolism, and therefore diet, are inextricably linked. And, as discussed on this site in the past, there is evidence that altering diet can impact cancer treatments as in the work that looked at chemo response and fasting. There is another reason for looking at this book - the authors (Professor Tony Howell and Dr Michelle Harvie) are both working in breast cancer research, and are involved specifically in helping patients reduce their chances of getting the disease or reducing the risk of recurrence. One of the authors, Tony Howell, is well known to regular readers of this site for his work on the reverse Warburg effect and his association with Michael Lisanti and the development of new theories that link cancer with metabolism.

That said, this is primarily a book about diets and losing weight rather than a book specifically about cancer. Although the links to cancer are there in the text, and many of the patient stories include mention of cancer, the main aim is to help readers lose weight and keep it off. And, in doing so, to reap the overall health benefits across the board.

So, what is the 2-day Diet, and how does it differ from the thousands of other diet books on the market? A key point to make up front is that this is a diet that's been backed up by clinical data. There are no celebrity endorsements, no one selling expensive supplements or foods, no hand waving or bold claims unsupported by evidence. This is a diet that has been shown to work, it's that simple. Simple too is the basic idea behind the diet - it's simpler to stick to a strict diet for two days per week than it is for seven. And, importantly, the changes induced by a strict two day a week diet are significant enough to cause changes in body weight, glucose tolerance, mood and so on.